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Una síntesis enantiospecífica de isoneoanfilectano confirma su estructura tricíclica tensa

Natalie C Dwulet¹, Zeinab Chahine², Karine G Le Roch²

¹Department of Chemistry, University of California, Irvine, California 92697-2025, United States.

Journal of the American Chemical Society

|February 2, 2023

Resumen

Los investigadores sintetizaron el raro isocyanoterpene isoneoamphilectano y sus diastereómeros. Este trabajo aclara el producto natural forjado

Área de la Ciencia:

Química orgánica
Síntesis de productos naturales

Sus antecedentes:

El isoneoanfilectano es un raro producto natural de isocyanoterpenos con un sistema de anillos tensados.
Un hipotético vínculo biosintético con compuestos relacionados sugirió una posible asignación errónea en su estructura reportada.

Objetivo del estudio:

Para lograr la síntesis total de isoneo-anfilectano.
Investigar posibles errores estructurales mediante la síntesis de diastereómeros no naturales.
Explorar nuevas metodologías sintéticas para la construcción de sistemas policíclicos tensados.

Principales métodos:

Síntesis total de isoneoanfilectano y dos diastereómeros no naturales.
Desafiando la epimerización cis-trans de las decalones.
Nuevo reordenamiento del tipo pinacol de sulfito cíclico para la formación de anillos de tensión.
Adición Mukaiyama-Michael estereocontrolada y eliminación regioselectiva.
Hidroazidación de alqueno para la formación de isonitril terciario.
Los análisis computacionales guiaron la planificación sintética y el control estereoquímico.

Principales resultados:

Síntesis exitosa de isoneoanfilectano y sus diastereómeros no naturales.
Desarrollo de un nuevo reordenamiento cíclico de sulfito para acceder al núcleo tensado.
Demostración de las principales transformaciones estereoselectivas y regioselectivas.
Confirmación de la estructura propuesta del isoneoanfilectano mediante síntesis.

Conclusiones:

La vía sintética proporciona acceso al isoneoanfilectano y sus análogos.
El estudio valida la estructura propuesta y ofrece información sobre su estereoquímica.
Se desarrollaron nuevos métodos sintéticos para construir productos naturales complejos y tensos.

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